Sheet metal roofing



July 18, 1939. w. 'r. WILLIAMS 2,166,275

SHEET METAL ROOFING Filed Nov. 17, 1936 gluon Mot W/LL/AN T WILL/A H5 Patented July 18, 1939 UNITED STATES PATENT OFFICE 2 Claims.

' The present invention relates to sheet metal roofing and more particularly to a roofing of this character. provided with a novel overlapping structure for preventing siphonic or capillary attraction therebetween.

Heretofore sheet metal roofing has been constructed having overlapping portions with means for preventing siphonic and capillary attraction in the form of an air space between the overlapped portions. However, these structures have the disadvantage of arranging the channel means for preventing the capillary attraction in such a manner that a leak through the nail holes is likely to occur. Stated in another manner, the

channels provided in the overlapped joints for preventing capillary attraction in the aforementioned construction are disposed in such a manner, that before the'water may be drawn over the risers or ridges employed and reaches the channel designed to break the siphon, it must necessarily pass over the top of the riser or ridge and start downwardly over the other side and in so doing will necessarily have to pass the nail holes provided for securing the overlapped joints together. It has been found that since the nail hole in the undersheet is larger than the hole in the top overlapped sheet because of the metal driven down by the nail in going through the first lap makes an impression and frequently so a break through on the undersheet, that the water in going over the top of the ridge will leak through the nail hole in the undersheet thus causing a leak.

It is, therefore, one of the objects of the pres- 3; ent invention to provide a structure for breaking the siphon, or eliminating capillary attraction which will overcome the aforementioned disadvantage and break the siphon or capillary attraction before the water reaches the top of .gthe ridge or riser thus preventing the water from reaching the nail holes, and the likelihood of a subsequent leak.

In the accompanying drawing wherein corresponding parts are designated by similar reference numerals throughout:-

Figure 1 is a fragmentary perspective view partly in section of a sheet metal roofing embodying the features of the present invention.

Figure 2 is a detail fragmentary vertical sec 5,, tional View taken through the overlapped joint of the sheet metal roofing.

Figure 3 is a fragmentary perspective view partly in section illustrating the construction of one of the ridges of the joints.

{,3 Figure l is a fragmentary perspective view partly in section of the top overlapping ridge of the joint.

In the accompanying drawing wherein for the purpose of illustration there is shown a preferred embodiment of the invention, the reference nu- 5 meral 5 generally designates a roof, which may be of any general construction and to which there is secured a sheet metal roofing formed of overlapped sections 6 and 8.

As will be observed, the roofing is formed of 10 overlapped sheet metal sections of rectangular or any other shape desired. Each section is provided with upstanding spacedly disposed ridges II] which have a fiat upper portion l2 and diverging side portions l4 and IS, the side por- 15 tions merging with the flat body portion of the roof sections.

As will be noted, in the usual construction each roof section is provided with a plurality of such ridges, and in the formation of the com' :0 pleted roof, the sections are secured together in overlapped relationship. As has been hereinbefore set forth, in overlapping the free ends of the sheet sections capillary attraction of the water is effected and it is to provide a novel strucg5 ture forming the subject matter of this application which will interrupt such capillary attraction.

Referring to Figures 2, 3 and 4 it will be observed that the free end of each sheet metal :50 section 6 and 8 are provided with ridges, the ridges as shown in these figures being adapted to be disposed in overlapped relationship. The ridge formed on the free end of the section 8 is provided with a flat upper portion l8 and diverging side portions 20, it being noted that this ridge is of the same general construction as the ridge l0 and when placed in overlapping relationship with the lower ridge which will be hereinafter described forms a ridge of the same construction as the ridge l0 thereby making a uniform. roof.

The free end of the section 6 is provided with a ridge having an upstanding fiat top portion 26, a diverging outer side 28 the oppositely disposed side 30 being provided with transversely extending steps 30 and 32.

Thus referring to Figure 2 it will be seen that when the section 8 is placed in alignment with the section 6 and the ridges placed in overlapping relationship the free end portion 28 and the inner side 20 are in abutting relationship, while the outermost upper side 20 contacts the knee portion of the'steps terminating adjacent the bottom of the section 6 thereby on the inner side of the overlapped ridges presenting air spaces therebetween.

It is thought well to note that when the upper ridge is placed in overlapping relationship on the lower ridge and. the same subsequently connected together through the medium of the usual nail 34 the space defined by the steps 30 and 32 will interrupt or prevent capillary attraction of water entering at the point indicated by the arrow in Figure 2 and thus prevent the water from reaching the nail hole caused by the nail 34. As hereinbefore set forth when the nail 34 is inserted in the upper ridge and subsequently through the lower ridge the material punched from the upper ridge causes the hole in the lower ridge to be somewhat larger and by virtue of the positioning of the steps on the inner side 30 of the section 6 as distinguished from on the outer side 28 the water cannot enter the nail hole through the lower ridge and thereby cause a leak. In other words, as distinguished from the prior art the steps 30 and 32 are provided on the inner side 30 of the sections as distinguished from the outer side 20 to overcome this disadvantage.

While there is shown for the purpose of illustration a specific shaped ridge and step construction it will be apparent, that the invention is capable of various changes and modifications without departing from the spirit and scope thereof and that any modified form or shape of ridge overlapped construction may be effected without departing from the spirit of the invention and it is intended therefore that only such limitations shall be imposed thereon as are indicated in the prior art or in the appended claims.

What is claimed is:

1. In roofing of the character described a sheet of metal provided at one side with an integral upstanding ridge having a fiat top and diverging sides, the innermost side being provided with a centrally disposed step therein including a horizontal tread and vertical risers and the outermost side thereof being flat, a second sheet provided at one side with an integral upstanding ridge having a flat top and diverging flat sides, said second ridge being placed upon said first-named ridge in overlapping relationship, the outer side portion of the upper ridge having its central portion resting on the apex of the step of the underneath ridge, the free end thereof resting on the fiat surface of the sheet defining a pair of air spaces therebetween adapted to interrupt capillary attraction.

2. In roofing of the character described a sheet of metal provided at one side with an integral upstanding ridge having a flat top and diverging sides, the innermost side being provided with a centrally disposed step therein including a horizontal tread and vertical risers and the outermost side thereof being fiat, a second sheet provided at one side with an integral upstanding ridge having a fiat top and diverging fiat sides, said second ridge being placed upon said first-named ridge in overlapping relationship, the outer side portion of the upper ridge having its central portion resting on the apex of the step of the underneath ridge, the free end thereof resting on the fiat surface of the sheet defining a pair of air spaces therebetween adapted to interrupt capillary attraction, and means extending through the fiat top of each ridge for securing the sheets together.

WILLIAM T. WILLIAMS. 

